This invention relates to vacuum cleaner filter bags. In particular, this invention relates to vacuum cleaner filter bags impregnated with bactericide. More particularly, this invention relates to a vacuum cleaner filter bag that more effectively brings bacteria and bactericide into contact with one another.
Dirt-laden air flowing into a vacuum cleaner typically is contaminated with bacteria. If the bacteria are small enough compared to the filtering ability of the filter bag of the vacuum cleaner, the bacteria may pass through the filtering medium of the filter bag and escape from the filter bag with the exhausted air. Alternatively, if the bacteria are too large to pass through the filter bag, they will remain in the filter bag where they will be free to multiply. In the latter case, eventually there may be enough bacteria to cause an unpleasant odor. In addition, some of the bacteria may escape, or they may be released when the filter bag is changed. Similarly, if for any reason a user must open a filter bag to examine its contents, the user could release the bacteria. This is the case with both disposable vacuum cleaner filter bags, which typically are made from one or more layers of filter paper, and reusable cloth vacuum cleaner filter bags.
It is known to treat the material of a vacuum cleaner filter bag with a bactericidal agent to kill bacteria. While this may be effective when the filter bag is new, and substantially all dirt entering the filter bag contacts the wall and the bactericidal agent, it is not true in a filter bag that has been used for any measurable length of time, because a "cake" of dust and dirt builds up on the interior walls of the filter bag, preventing bacteria from contacting the bactericidal agent. Therefore, treating the walls of a vacuum cleaner filter bag is effective substantially only to prevent bacterial colonies from "growing through" the filter bag.
It is also known in the case of a hand-held vacuum cleaner to provide a tube for introducing a bactericidal fluid. The tube extends into the dirt collection chamber and has a wick bag at the end thereof through which the bactericidal fluid is introduced into the airstream within the chamber. In one embodiment, the wick bag has a plurality of capillary tubes extending therefrom which move in the airstream to enhance the dispersion of the fluid.
It would be desirable to be able to provide a vacuum cleaner filter bag treated with a bactericidal agent that is able to kill bacteria even after a cake of dust and dirt has formed on the interior walls of the filter bag.